[PATCH] sd: read-only switch
Support for the read-only switch on SD cards which must be enforced by the
host.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 294961a..725c6ad 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -413,8 +413,7 @@
card->cid.month = UNSTUFF_BITS(resp, 8, 4);
card->cid.year += 2000; /* SD cards year offset */
- }
- else {
+ } else {
/*
* The selection of the format here is based upon published
* specs from sandisk and from what people have reported.
@@ -494,8 +493,7 @@
csd->capacity = (1 + m) << (e + 2);
csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4);
- }
- else {
+ } else {
/*
* We only understand CSD structure v1.1 and v1.2.
* v1.2 has extra information in bits 15, 11 and 10.
@@ -738,10 +736,20 @@
err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
if (err != MMC_ERR_NONE)
mmc_card_set_dead(card);
- else
+ else {
card->rca = cmd.resp[0] >> 16;
- }
- else {
+
+ if (!host->ops->get_ro) {
+ printk(KERN_WARNING "%s: host does not "
+ "support reading read-only "
+ "switch. assuming write-enable.\n",
+ mmc_hostname(host));
+ } else {
+ if (host->ops->get_ro(host))
+ mmc_card_set_readonly(card);
+ }
+ }
+ } else {
cmd.opcode = MMC_SET_RELATIVE_ADDR;
cmd.arg = card->rca << 16;
cmd.flags = MMC_RSP_R1;
@@ -833,24 +841,23 @@
int err;
u32 ocr;
- host->mode = MMC_MODE_MMC;
+ host->mode = MMC_MODE_SD;
mmc_power_up(host);
mmc_idle_cards(host);
- err = mmc_send_op_cond(host, 0, &ocr);
+ err = mmc_send_app_op_cond(host, 0, &ocr);
/*
- * If we fail to detect any cards then try
- * searching for SD cards.
+ * If we fail to detect any SD cards then try
+ * searching for MMC cards.
*/
- if (err != MMC_ERR_NONE)
- {
- err = mmc_send_app_op_cond(host, 0, &ocr);
+ if (err != MMC_ERR_NONE) {
+ host->mode = MMC_MODE_MMC;
+
+ err = mmc_send_op_cond(host, 0, &ocr);
if (err != MMC_ERR_NONE)
return;
-
- host->mode = MMC_MODE_SD;
}
host->ocr = mmc_select_voltage(host, ocr);
diff --git a/drivers/mmc/mmc_block.c b/drivers/mmc/mmc_block.c
index d4eee99..fa83f15 100644
--- a/drivers/mmc/mmc_block.c
+++ b/drivers/mmc/mmc_block.c
@@ -95,6 +95,10 @@
if (md->usage == 2)
check_disk_change(inode->i_bdev);
ret = 0;
+
+ if ((filp->f_mode & FMODE_WRITE) &&
+ mmc_card_readonly(md->queue.card))
+ ret = -EROFS;
}
return ret;
@@ -403,9 +407,10 @@
if (err)
goto out;
- printk(KERN_INFO "%s: %s %s %dKiB\n",
+ printk(KERN_INFO "%s: %s %s %dKiB %s\n",
md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
- (card->csd.capacity << card->csd.read_blkbits) / 1024);
+ (card->csd.capacity << card->csd.read_blkbits) / 1024,
+ mmc_card_readonly(card)?"(ro)":"");
mmc_set_drvdata(card, md);
add_disk(md->disk);
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 538e8c8..0e9ec01 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -48,6 +48,7 @@
#define MMC_STATE_DEAD (1<<1) /* device no longer in stack */
#define MMC_STATE_BAD (1<<2) /* unrecognised device */
#define MMC_STATE_SDCARD (1<<3) /* is an SD card */
+#define MMC_STATE_READONLY (1<<4) /* card is read-only */
u32 raw_cid[4]; /* raw card CID */
u32 raw_csd[4]; /* raw card CSD */
struct mmc_cid cid; /* card identification */
@@ -58,11 +59,13 @@
#define mmc_card_dead(c) ((c)->state & MMC_STATE_DEAD)
#define mmc_card_bad(c) ((c)->state & MMC_STATE_BAD)
#define mmc_card_sd(c) ((c)->state & MMC_STATE_SDCARD)
+#define mmc_card_readonly(c) ((c)->state & MMC_STATE_READONLY)
#define mmc_card_set_present(c) ((c)->state |= MMC_STATE_PRESENT)
#define mmc_card_set_dead(c) ((c)->state |= MMC_STATE_DEAD)
#define mmc_card_set_bad(c) ((c)->state |= MMC_STATE_BAD)
#define mmc_card_set_sd(c) ((c)->state |= MMC_STATE_SDCARD)
+#define mmc_card_set_readonly(c) ((c)->state |= MMC_STATE_READONLY)
#define mmc_card_name(c) ((c)->cid.prod_name)
#define mmc_card_id(c) ((c)->dev.bus_id)
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 845020d..8c5f713 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -62,6 +62,7 @@
struct mmc_host_ops {
void (*request)(struct mmc_host *host, struct mmc_request *req);
void (*set_ios)(struct mmc_host *host, struct mmc_ios *ios);
+ int (*get_ro)(struct mmc_host *host);
};
struct mmc_card;